1. Field of the Invention
This invention relates generally to folding type fabric reflection devices, as used in photography and graphic arts to produce shadow and highlight reducing indirect lighting effects upon a subject or area, whereby an external light source such as an electronic flash or incandescent lamphead is attached to the reflector and its beam directed onto a reflective surface thereof to be diffused as scattered rays reaching the subject area as indirect "bounce" light.
This invention presents a new and novel type collapsible reflector assembly having a methodology for producing greater illumination efficiency and directional controllability in achieving similar indirect lighting effects by "ricochet" lumens.
2. Cross Reference Related to Application
Patent and Trade Mark Office's Disclosure Document Program, Registration No. 104505, Mail Room date Nov. 30, 1981.
[Disclosure accompanied by photographs and test results of prototype.]
3. Description of the Prior Art
Heretofore there were only three basic types or shapes of folding reflectors used by photographers for producing indirect lighting effects with external light sources or ambient sunlight: The first type being merely a framework having a reflective fabric material streached upon it to disperse the beam from a separated light source or rays from the sun; however, great care is required with placement of the lamphead to avoid a mirror-image of the beam being reflected into the scene by the rays being reflected but not diffused. Therefore, the flat type reflector is generally used only secondarily to redirect primary illumination back onto the scene. Mounting the flat reflector and the separate light source additionally make this type virtually obsolete.
The second type folding reflector is the more commonly used round shape umbrella for producing indirect or "bounce" light from the beam of an external source attached to the umbrella's center-pole of these versions of the traditional rain/sun style umbrella, which all require a separate clamping device to mount the umbrella onto a suitable light-stand, and which likewise clamps the center-pole in a cantilevered manner. The external light source's weight is then likewise cantilevered, since it is attached to the opposite end of the center-pole by another clamping device or a double-ball-and-socket arrangement, either of which may be a separate part requiring somewhat difficult attachment and alignment of the light source, same usually being an electronic flash unit triggered to fire by a photo-sensitive slave reacting to an on-camera flash, which likewise must be attached to the umbrella or light source. Once assembled the umbrella still must be angled and positioned, and often re-balanced, by adjusting these devices, as abovesaid. Therefore, the opening, mounting and stabilizing such umbrellas and the attached light source becomes quite difficult under many studio and location conditions, as does the necessary disassembly before such units can be furled for transport or storage, same being especially difficult in maintaining their many loose parts which are easily mislaid or lost since no provision is made for them in the carrying cases usually provided with such umbrellas. In addition to these structures and their elements being awkward to set-up, their physical size and top-heavy balance makes them precarious to work with in confined areas. Other physical and inherent problems with such umbrellas affect their reflecting efficiency adversly, due to the source beam being aimed toward the interior of the opened hexagonal or octagonal reflective cover in an off-center manner by the source being attached atop the conter-pole. Further, since such covers are generally woven of simulated metallic thread, some of the beam's rays pass through the weave while others are overly deflected off of exposed ribs, hinged-spreader for the ribs, center-pole and the lamphead itself, thus many lumens are dispersed ineffectually. Furthermore, due to their usual 36" to 52" reflector size of 9 to 11 square-feet and their lack of control of the reflected illumination produced as virtually random rays, such structures require high input candlepower to be effective on a large subject or scene area.
The third and last type of folding fabric covered reflector for producing indirect lighting is merely a modification or variation of the conventional umbrella, excepting that it has only four triangular panels forming a square reflective cover suppoted by four ribs, but having its ribs, hinged rib-spreader, center-pole and the obstructing lamphead attaching devices cluttering the inner-surface of the reflector to thereby reduce its reflective efficiency. Like the round type umbrellas, the external light source is attached to the center-pole and its beam directed to impact the center of the inverted pyramidal shape reflective surface; however, most of these square versions have an improved system for mounting the light source so that the actual lamphead is centered along the center-pole. However, in order to accomplish this improvement of off-centering the remaining mass of the usual self-contained flash or the lamphead and its support for the larger strobe units having separate power-packs, two additional loose parts are required to be attached upon the center-pole. The first member is L-shaped and secured to the center-pole by a set-screw, then the second part is fitted into a hole in the lower section of the L-shape, which allows this rod-like element to be moved up or down and secured by another set-screw or thumb-screw, after separately attaching the lamphead atop the sliding rod, or else the parts may be assembled before affixing the top of the L-shape member onto the center-pole. Thereafter additional adjustments are required to balance the cantilevered weight at each end of the center-pole, plus re-adjusting the separate clamping unit holding the assembly upon the necessary light-stand, in order to angle the device. But, as with the round umbrellas, most of the loosely woven metallic thread cover allows some of the rays to pass through the reflector, rather than being directly bounced backward upon a scene. Further, the rays which are thereby reflected are widely scattered, due to the low angles of the four reflecting panels, thus the peripheral areas of the reflected illumination are considerably weakened in lumen intensity; therefore, the square umbrealla gives its best results in lighting very wide scene areas. Furthermore, the wide-spreading pattern of indirect lighting thus produced lacks the "wrap-around effects" developed by the round-umbrellas, which is a desirable feature in subject lighting.
Despite their many disadvantages, such umbrellas are the current state-of-the-art for fabric covered reflectors.